如何避免mysql的double自动转为科学计数法表示

Posted 2023-05-17

参考技术A 如何避免mysql的double自动转为科学计数法表示
Sub FillColumn(fg As vsFlexGrid, ByVal c As Long, ByVal t As String, ByVal s As String)

Dim r&, i&, cnt&
ReDim lst(0) As String

' build list
cnt = 0
i = InStr(s, "|")
While i > 0
lst(cnt) = left(s, i - 1)
s = Mid(s, i + 1)
cnt = cnt + 1
ReDim Preserve lst(cnt) As String
i = InStr(s, "|")
Wend
lst(cnt) = s

' set values
fg.Cell(flexcpText, 0, c) = t
For r = fg.FixedRows To fg.Rows - 1
i = (Rnd() * 1000) Mod (cnt + 1)
fg.Cell(flexcpText, r, c) = lst(i)
Next

' do an autosize
fg.AutoSize c, , , 300
End Sub

FillColumn hfxgrid ""Proposals|Demos|Social|Trips|Projects""本回答被提问者采纳

Java中double类型如何避免显示为科学计数法

//double的金额类型显示为科学计数法
    //这里以String转换double举例
    public static void main(String[] args) 

        //double类型在小数点前位数大于7位时自动转换为科学计数法表示
        String amountStr = "12345678.12";

        double amount = Double.parseDouble(amountStr);
        System.out.println(amount);//1.234567812E7

        BigDecimal bigDecimal = new BigDecimal(amountStr);
        System.out.println(bigDecimal);//12345678.12

        //由此，想要避免科学计数法有以下两种常用方法
        //1、直接使用String不适用double
        //2、使用BigDecimal来作为金额的数据类型（在对应数据库的数据类型时，BigDecimal和double没有不同）；private BigDecimal amount;


        //但是直接通过new BigDecimal(amountStr)，可能会因为String的值导致报错
        //例如null
        //建议金额为String时，先转double
        String amountStr1 = "12345678.12";

        double amount1 = Double.parseDouble(amountStr);
        BigDecimal bigDecimal1 = new BigDecimal(amount1);
        System.out.println(bigDecimal1);//12345678.12

        String amountStr2 = null;

        double amount2 = Double.parseDouble(amountStr2);
        BigDecimal bigDecimal2 = new BigDecimal(amount2);
        System.out.println(bigDecimal2);//-1.0